1. Field:
This invention pertains to hair treatment. It is specifically directed to an additive for water-based hair treatment compositions and provides a protein-based additive including keratin, collagen and amino acids.
2. State of the art:
The formulation of hair treatment compositions such as shampoos; setting lotions, sprays and dressings; tonics and conditioners; colorants; permanent wave solutions and strengtheners; and straighteners is a well developed art. The textbook Harry's Cosmeticology, edited by J. B. Wilkinson and R. J. Moore, Chemical Publishing Company, New York (Seventh edition, 1982) includes an approximately 200 page section devoted to human hair, its structure, nutrition and care. This text discloses the common constituents of all of the aforementioned hair treatment compositions and the practical considerations involved in their formulation and application. Each of the several chapters devoted to specific categories of compositions; e.g., shampoos, ends with a bibliography of references pertinent to that category. Other portions of the book describe product ingredients; e.g., surface active agents, antioxidants and emulsions, as well as their selection and incorporation in hair treatment products. This book and its bibliographies disclose the state of the art pertaining to the manufacture and application of hair treatment products and are incorporated by reference to the extent that their respective teachings are applicable to this disclosure.
The Cosmetic, Toiletry and Fragrance Association, Inc. of Vermont Avenue, N.W., Washington, D.C. 20005 publishes a CTFA cosmetic ingredient dictionary. References in this disclosure to CTFA names correspond to the names listed in the third edition (1982) of that dictionary.
Among the constituents which are currently available to formulators of hair treatment compositions is a class known as "soluble keratin." The materials of this class which are of most interest to hair treatment are those referred to within the CTFA adopted name system of nomenclature as "soluble animal keratin" which have molecular weights greater than about 100,000. An exemplary such material is that sold under the trademark "KERASOL" by Croda, Inc., 183 Madison Avenue, New York, New York. "KERASOL" has a molecular weight of about 125,000, and a structure which approximates that of human hair. It is soluble in water and is typically supplied as a 15 percent active ingredients aqueous solution. It has been incorporated into a wide range of water-based hair care products, including permanent wave solutions, shampoos and conditioners, although in shampoos and conditioners it will not covalently bond to the hair. Nevertheless, its film-forming properties are known to improve the body and sheen, as well as the manageability and combing characteristics, of hair.
Another family of protein compounds used by formulators of hair treatment compositions is the protein quaternary compounds with specific gravities greater than about 1. Croda, Inc. supplies a representative such compound under the trademark "CROQUAT M." This product is a viscous amber liquid containing about 40 to about 45 percent by volume cocoyl quaternized protein, the remaining volume consisting of volatiles. It is water soluble, and in 10 percent aqueous solution has a pH in the range of about 4 to about 5.5. Its CTFA adopted name is "cocodimonium hydrolyzed animal collagen."
It is known that the hydrolysis of pure silk fiber can produce a mixture of the individual amino acids which naturally occur in silk ("silk amino acids"). The major such silk amino acids are glycine, alanine, serine, and tyrosine. The silk amino acid mixture resulting from silk hydrolysis is of low molecular weight and of specific gravity above about 1. Croda, Inc. supplies a silk amino acid mixture under the tradename "CROSILK LIQUID" which typically has a solids content in the range of about 27 to about 31 percent by weight and an ash content of about 12 to about 16 percent by weight. A typical amino acid spectrum of "CROSILK LIQUID" is reported in Table A.
TABLE A ______________________________________ Amino Acid Percent by Weight ______________________________________ ALANINE 28.4 GLYCINE 34.7 VALINE 2.0 LEUCINE 1.2 PROLINE 1.2 TYROSINE 0.6 PHENYLALANINE 0.9 SERINE 15.4 THREONINE 1.9 ARGININE 1.5 ASPARTIC ACID 4.7 GLUTAMIC ACID 4.1 ISOLEUCINE 0.8 LYSINE 1.4 HISTIDINE 0.8 CYSTINE 0.1 METHIONINE 0.2 99.9 ______________________________________